Virtual machines are very low on entropy and they block very easily even at boot time (deny user login for a while (can be minute)). The current way to solve this is specifying the random number generator : - at all images (user) - at all flavors (admin) - in all nova.conf (ospd/admin) Expected solution: Add an option to nova.conf which allows to globally use rnd generator unless the user either at boot time or at image creation time explicitly disables it.
We're generally reluctant to add nova.conf driven configuration for things that affect instances since it can cause issues with migrations. I'm guessing turning on the RNG on by default would be a better approach. That's being tracked in another BZ so I'm going to close this as a duplicate and track the work there. *** This bug has been marked as a duplicate of bug 1608760 ***